The-present invention relates generally to hard surface cleaners. In particular, the present invention relates to hard surface cleaners that are effective to clean soils normally found in household, industrial and/or institutional environments and which exhibit improved cleaning, high foaming and less temperature dependent Theological properties.
Hard surface cleaners that clean soils commonly found in household, industrial and/or institutional environments are known. Specifically, cleaners are known which are capable of cleaning a variety of soils, such as petroleum and fatty acids, particulate, oxidizable, proteinaceous triglyceride soils or soils normally found on hard surfaces such as dishes, glasses, tiles, fiberglass, steel, aluminum, plastic, wood, cement and the like. While these known formulations may work adequately under normal conditions, they are generally deficient in low temperature applications since their flow characteristics are susceptible to significant changes in temperature. In addition, many known hard surface cleaners are typically incompatible with sanitizing solutions as they tend to deactivate the active sanitizing ingredient(s).
U.S. Pat. No. 4,663,0821 discloses a high pH water-based industrial cleaning composition comprising a series of anionic surfactants, builders and alkalinity agents. U.S. Pat. No. 4,904,359 discloses high sudsing liquid detergent compositions which contain an anionic surfactant and a polymeric surfactant containing ether linkages, the anionic surfactant forming stable complexes with the polymeric surfactant for improved grease handling.
1 The entire content of each patent and publication cited herein is expressly incorporated by reference. 
International Application No. 91/10718 discloses a composition requiring at least one anionic surfactant and at least one monocarboxylic acid. EPO 0392394B1 discloses a degreasing composition and a surfactant comprises of a nonionic surfactant of the polyoxyalkylene ether-type with a phosphate polyethylene oxide adduct. This mix is combined with a necessary amount of alkali builder of varying types. The phosphate moiety is responsible for increasing the generation of foam and, as is known, represents an environmental concern.
U.S. Pat. Nos. 5,518,648 and 5,382,376 disclose detergent compositions containing ethylene oxide-propylene oxide (EO/PO) block copolymers as surfactants. U.S. Pat. No. 5,536,438 discloses a cleaning composition containing four nonionic surfactants (fatty alcohol ethoxylates of different HLB values. U.S. Pat. No. 5,501,816 discloses ternary surfactant blends comprised of alcohol alkoxylate with a fatty alcohol moiety, alkylphenol alkoxylates and alkyl oxyethylate.
Broadly, the present invention is embodied in hard surface cleaning formulations comprised of a hard surface cleaning effective amount of an associative thickener and at least two nonionic surfactants selected from the group consisting of ethoxylated alcohols and ethoxylated fatty acids. The hard surface cleaning formulations of the present invention advantageously exhibit a high foam volume of at least about 150 cc when a 100 ml aqueous solution containing about 0.1 wt. % of the formulation is agitated at 2,500 rpm for a cumulative agitation period of about 1200 seconds. In addition, the formulations of the present invention exhibit satisfactory foam stability sufficient to clean at least about 25 plates (ASTM D4009-92).
Preferably, the associative thickener is the reaction product of a C6 or greater epoxide compound with a polyoxyalkylene polyol. The ethoxylated alcohols and ethoxylated fatty acids each most preferably contain C8 to C18 carbon chains which are ethoxylated with between about 3 to about 20 moles of ethylene oxide. Especially preferred ethoxylated alcohols are fatty alcohols having oxyethylate moieties of the general formula R(OCH2CH2)xOH, wherein R is a C10 to C13 branched or straight chain alkyl group and x is within the range of about 4 to about 10. The ethoxylated alcohols which are employed in accordance with the present invention do not necessarily require the presence of only ethylene oxide groups. Instead, the ethoxylated alcohols usefully employed in the formulations of the present invention may have C3 or higher alkylene oxide groups present (for example, propylene oxide), in addition to ethylene oxide groups.
These and other aspects and advantages will become more apparent after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof.